See the file 'config.sub' for the possible values of each field. If
'config.sub' isn't included in this package, then this package doesn't
need to know the machine type.
If you arebuilding compiler tools for cross-compiling, you should
use the option '--target=TYPE' to select the type of system they will
produce code for.
If you want touse a cross compiler, that generates code for a
platform different from the build platform, you should specify the
"host" platform (i.e., that on which the generated programs will
eventually be run) with '--host=TYPE'.
Sharing Defaults
================
If you want to set default values for 'configure' scripts to share,
you can create a site shell script called 'config.site' that gives
default values for variables like 'CC', 'cache_file', and 'prefix'.
'configure' looks for 'PREFIX/share/config.site' if it exists, then
'PREFIX/etc/config.site' if it exists. Or, you can set the
'CONFIG_SITE' environment variable to the location of the site script.
A warning: not all 'configure' scripts look for a site script.
Defining Variables
==================
Variables not defined in a site shell script can be set in the
environment passed to 'configure'. However, some packages may run
configure again during the build, and the customized values of these
variables may be lost. In order to avoid this problem, you should set
them in the 'configure' command line, using 'VAR=value'. For example:
./configure CC=/usr/local2/bin/gcc
causes the specified 'gcc' to be used as the C compiler (unless it is
overridden in the site shell script).
Unfortunately, this technique does not work for 'CONFIG_SHELL' due to an
Autoconf limitation. Until the limitation is lifted, you can use this
workaround:
CONFIG_SHELL=/bin/bash ./configure CONFIG_SHELL=/bin/bash
'configure' Invocation
======================
'configure' recognizes the following options to control how it
operates.
'--help'
'-h'
Print a summary of all of the options to 'configure', and exit.
'--help=short'
'--help=recursive'
Print a summary of the options unique to this package's
'configure', and exit. The 'short' variant lists options used only
in the top level, while the 'recursive' variant lists options also
present in any nested packages.
'--version'
'-V'
Print the version of Autoconf used to generate the 'configure'
script, and exit.
'--cache-file=FILE'
Enable the cache: use and save the results of the tests in FILE,
traditionally 'config.cache'. FILE defaults to '/dev/null' to
disable caching.
'--config-cache'
'-C'
Alias for '--cache-file=config.cache'.
'--quiet'
'--silent'
'-q'
Do not print messages saying which checks are being made. To
suppress all normal output, redirect it to '/dev/null' (any error
messages will still be shown).
'--srcdir=DIR'
Look for the package's source code in directory DIR. Usually
'configure' can determine that directory automatically.
'--prefix=DIR'
Use DIR as the installation prefix. *note Installation Names:: for
more details, including other options available for fine-tuning the
installation locations.
'--no-create'
'-n'
Run the configure checks, but stop before creating any output
files.
'configure' also accepts some other, not widely useful, options. Run
'configure --help' for more details.
'config.sub' isn't included in this package, then this package doesn't
need to know the machine type.
If you arebuilding compiler tools for cross-compiling, you should
use the option '--target=TYPE' to select the type of system they will
produce code for.
If you want touse a cross compiler, that generates code for a
platform different from the build platform, you should specify the
"host" platform (i.e., that on which the generated programs will
eventually be run) with '--host=TYPE'.
Sharing Defaults
================
If you want to set default values for 'configure' scripts to share,
you can create a site shell script called 'config.site' that gives
default values for variables like 'CC', 'cache_file', and 'prefix'.
'configure' looks for 'PREFIX/share/config.site' if it exists, then
'PREFIX/etc/config.site' if it exists. Or, you can set the
'CONFIG_SITE' environment variable to the location of the site script.
A warning: not all 'configure' scripts look for a site script.
Defining Variables
==================
Variables not defined in a site shell script can be set in the
environment passed to 'configure'. However, some packages may run
configure again during the build, and the customized values of these
variables may be lost. In order to avoid this problem, you should set
them in the 'configure' command line, using 'VAR=value'. For example:
./configure CC=/usr/local2/bin/gcc
causes the specified 'gcc' to be used as the C compiler (unless it is
overridden in the site shell script).
Unfortunately, this technique does not work for 'CONFIG_SHELL' due to an
Autoconf limitation. Until the limitation is lifted, you can use this
workaround:
CONFIG_SHELL=/bin/bash ./configure CONFIG_SHELL=/bin/bash
'configure' Invocation
======================
'configure' recognizes the following options to control how it
operates.
'--help'
'-h'
Print a summary of all of the options to 'configure', and exit.
'--help=short'
'--help=recursive'
Print a summary of the options unique to this package's
'configure', and exit. The 'short' variant lists options used only
in the top level, while the 'recursive' variant lists options also
present in any nested packages.
'--version'
'-V'
Print the version of Autoconf used to generate the 'configure'
script, and exit.
'--cache-file=FILE'
Enable the cache: use and save the results of the tests in FILE,
traditionally 'config.cache'. FILE defaults to '/dev/null' to
disable caching.
'--config-cache'
'-C'
Alias for '--cache-file=config.cache'.
'--quiet'
'--silent'
'-q'
Do not print messages saying which checks are being made. To
suppress all normal output, redirect it to '/dev/null' (any error
messages will still be shown).
'--srcdir=DIR'
Look for the package's source code in directory DIR. Usually
'configure' can determine that directory automatically.
'--prefix=DIR'
Use DIR as the installation prefix. *note Installation Names:: for
more details, including other options available for fine-tuning the
installation locations.
'--no-create'
'-n'
Run the configure checks, but stop before creating any output
files.
'configure' also accepts some other, not widely useful, options. Run
'configure --help' for more details.


